It sounds as if Dil is a rather a soul-less besom, not just controling her life but wanting to control yours too.
I wouldn't fancy Christmas with anyone who told me she wanted to get it over with and by implication, me too.
How does she think that makes you feel? If she thinks at all, which I doubt.
Don't allow yourself to be a duty that has to be got out of the way as quickly as possible, you deserve better.
And why doesn't your son give her the hard word and point out that you're his mother and deserve love and respect?
Surely she doesn't control him too?
I'd go to your daughter's if I were you and take the dogs, they love you unconditionally.
Let the dil pull her own cracker.
Just tell her, you've already got it over with.
Yes, I know, Treelover you poor thing, you risk losing contact with the grand-children if you do any of this but I do hate what I see as 'elder abuse' - because controlling someone, especially at Christmas, and deliberately making them feel unhappy and unwanted, is exactly what this is.